disease Flashcards
effect of HIV
aids it affected by hiv
Spread by direct contact with infected body fluids e.g. blood,
semen, breast milk.
Destroys white blood cells making the individual immunodeficient and increasingly susceptible to other diseases. Leads to AIDS.
Use of condoms and protected sex.
Needle exchange.
Screening blood for HIV.
Deterring infected mothers from
breastfeeding.
effect of chlamydia
if left untreated Causes infertility in adults, conjunctivitis and
lung problems in babies.
Antibiotics like tetracycline
Sexually transmitted, use condoms to prevent spread.
tablets
as tetracycline or erythromycin.
effect of malaria
Destroys red blood cells causing fever.
Prevent the mosquitos biting and infecting people by:
* killing mosquitoes with insecticide
* releasing large numbers of infertile male mosquitoes
* biological control of mosquitoes
* use of mosquito nets and repellents.
penicillin
antibiotic
Pathogens are communicable, they can be spread by:
- contact
- aerosol
- body fluids
- water
- insects
- contaminated food.
types of microorganisms
● Bacteria
● Fungi (not all fungi are micro-organisms)
● Viruses
● Protists
pathogen
microorganism that causes disease
bacteria
single celled organism
structure of a virus
Their structure consists
of a central core of genetic material surrounded by a
protein coat. They do not contain a cytoplasm, nor a cell
membrane.
scientific names
chlamydia trachomatis (bacteria)
human immunodeficiency virus (virus)
plasmodium (protist)
acquired immunodeficiency syndrome
first line of defence
non specific prevents pathogen from entering the body
skin natural skin flora
blood clotting This seals wounds and stops the entry of microbes when the skin surface is cut.
2nd line of defence
immune system
types of white blood cells
phagocytes
engulf pathogens
lymphocytes which secrete antibodies and antitoxins (neutralise toxins
produced by the pathogen).
antigens
Antigens are molecules on the surface of all cells that are recognised by the immune system.
Pathogens have unique antigens on their surface. WBCs have specialised receptors which can
detect these foreign antigens on pathogens, triggering an immune response.
antibodies
Antibodies are proteins produced by lymphocytes in response to a foreign antigen. Each antibody
is specific to an antigen and binds to it. Antibodies cause the pathogen to clump together, disabling
them and facilitating ingestion by phagocy
memory cells
Memory cells are lymphocytes that remain in the body after a pathogen has been destroyed.
They provide immunity: if the body is re-infected, antibodies are produced more rapidly and the pathogen is destroyed before it can produce disease symptoms
vaccination
- Dead, weakened or inactivated pathogens are given to the patient.
- The antigens initiate an immune response resulting in the production of antibodies
- Memory cells are produced which remain in the body, providing long-term immunity
disadvantages of vaccines
Concerns about potential side effects/adverse reactions.
● Religious or cultural objections.
● Not guaranteed to work.
● May cause upset to children.
● May believe that vaccines are linked to other diseases such as autism, asthma etc.
what is an antibiotic
Antibiotics are substances produced by living organisms (e.g. fungi) that kill or inhibit the growth of
bacteria (no effect on viruses).
why are bacteria becoming resistant
Due to overprescription and antibiotic misuse (e.g. not completing the entire course), bacteria are
becoming increasingly resistant to antibiotics.
what is a highly resistant strain of bacteria
MRSA resistant to nearly all antibiotics
Control measures to prevent infection by MRSA:
● New patients screened for MRSA.
● Stringent hygiene measures in hospitals (hospital staff, patients and visitors).
Control measures to prevent the development of new resistant strains:
Prescribe antibiotics only when necessary.
● Ensure patients complete their antibiotic courses.
● Variation in the types of antibiotics prescribed.
what is a drug
A drug is a substance that affects chemical processes within the body they must undergo testing